Silicone elastomer gels have been used extensively to enhance the aesthetics of personal care formulations by providing a unique sensory profile upon application. Most silicone elastomer gels are obtained by a crosslinking hydrosilylation reaction of an SiH polysiloxane with another polysiloxane containing an unsaturated hydrocarbon substituent, such as a vinyl functional polysiloxane, or by crosslinking an SiH polysiloxane with a hydrocarbon diene. The silicone elastomers may be formed in the presence of a carrier fluid, such as a volatile silicone, resulting in a gelled composition. Alternatively, the silicone elastomer may be formed at higher solids content, subsequently sheared and admixed with a carrier fluid to also create gels or paste like compositions. Representative examples of such silicone elastomers are taught in U.S. Pat. Nos. 5,880,210, and 5,760,116.
While silicone elastomers have provided significant advances for improving personal care formulation, they possess several shortcomings that have limited their use. For example, silicone elastomers having mostly dimethyl siloxane content are less effective for gelling organic based solvents and carrier fluids. Silicone elastomer gel compositions having high dimethyl siloxane also have limited compatibility with many personal care ingredients. For example, the widely used sunscreen agent, octyl methoxycinnamate, has limited solubility in many of these silicone elastomer gels. Another problem is the reduction of viscosity of the silicone elastomer gel in the presence of such incompatible components. Thus, there is a need to identify silicone elastomers that can gel organic solvents. Furthermore, there is a need to identify silicone elastomer gels having improved compatibilities with many personal care ingredients, while maintaining the aesthetics associated with silicone organic elastomer gels. To this end, there have been many attempts to improve compatibilities of silicone elastomers with various personal care ingredients wherein alkyls, polyether, amines or other organofunctional groups have been grafted onto the silicone organic elastomer backbone. Representative of such organofunctional silicone elastomers are taught in U.S. Pat. Nos. 5,811,487 , 5,880,210 , 6,200,581, 5,236,986, 6,331,604 , 6,262,170 , 6,531,540, and 6,365,670.
However, there is still a need to improve the compatibility of silicone elastomer based gels, and in particular, with organic based volatile fluids and personal care ingredients. Such improved compatibility should not sacrifice sensory aesthetic profiles. Furthermore, the gelling or thickening efficiency of the silicone elastomer in a carrier fluid should be maintained or improved.
The present inventors have discovered silicone organic elastomers based on certain organopolysiloxane resins that provide gelled compositions of carrier fluids efficiently. The resulting gelled compositions also possess additional benefits, such as improved compatibilities with many common personal care ingredients, while maintaining sensory aesthetics.